The different types of hacker that exist today are listed in the table below.
|A Black Hat hacker concentrates on finding, and exploiting, the weaknesses in systems in order to perform malicious acts or to cause some kind of injury. All activities of the Black Hat hackers are considered crimes and so, where possible, prosecutions have, and continue to be, brought against this kind of hacker.
|A Computer Security Hacker is someone who specializes in work with the security mechanisms for computer and network systems. Particularly within the US, the subculture around such hackers is termed “network hacker subculture”, “hacker scene” or “computer underground”.
|A Cracker is a person who concentrates on finding weakesses in the security-related parts of software and hardware in order to disable the security and allow unauthorised use. Most activities of the cracker are illegal, however, they often go unprosecuted as the people whose software has been compromised have neither the resources nor the time to persue them.
|A Phreaker concentrates on finding, and exploiting, the weaknesses in telephone systems.
|An Open Source Hacker is a person who enjoys designing software and building programs with a sense for aesthetics and playful cleverness. These hackers have been responsible for creating the Open Source movement, a collection of computer programmers who collectively write software that is free to use and distribute.
|A White Hat hacker concentrates on finding the weaknesses in systems in order that the systems themselves may be fixed. These hackers are sometimes hired by corporations to find weaknesses in the corporation’s own products and so are not prosecuted for their work.
As the number of hackers has increased, and the seriousness of the hacker’s crimes has also increased, groups of programmers within US Academia and the homebrew clubs[Note 7] have been trying to distiguish and distance themselves from the criminal hackers and the criminal image of hacking. These groups are trying to reestablish the use of the general word “hacker” in its original sense – i.e. as a person who exercises great skill in creating or modifying software and getting the maximum benefit out of it. To read about this discussion in detail, please read Hacker Definition Controversy.